Preparation and Characterization of Electrosprayed Nanoparticles containing Ethyl Maltol Flavor

2021 ◽  
Vol 1042 ◽  
pp. 131-136
Author(s):  
Megdi Eltayeb

In this study, electrospraying is used to prepare electrosprayed multicomponent nanoparticles of ethylcellulose and stearic acid entrapping ethyl maltol. Electrospraying nanoparticles produced were ≤100 nm diameter and narrow size distribution (polydispersity index 0.26) is achieved. The ethyl maltol entrapment efficiency and yield were approximately 88% and 76%, respectively. The presence of ethyl maltol flavor within the polymeric electrosprayed nanoparticles was shown by Fourier transform infrared spectroscopy. The morphology of the electrosprayed multicomponent nanoparticles generated was studied by transmission electron microscopy.

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Noura El-Ahmady El-Naggar ◽  
Attiya Mohamedin ◽  
Sarah Shawqi Hamza ◽  
Abdel-Dayem Sherief

Biological method for silver nanoparticles synthesis has been developed to obtain cost effective, clean, nontoxic, and ecofriendly size-controlled nanoparticles. The objective of this study is extracellular biosynthesis of antimicrobial AgNPs using cell-free supernatant of a localStreptomycessp. strain SSHH-1E. Different medium composition and fermentation conditions were screened for maximal AgNPs biosynthesis using Plackett-Burman experimental design and the variables with statistically significant effects were selected to study their combined effects and to find out the optimum values using a Box-Behnken design. The synthesized AgNPs were characterized using UV-visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy. Rapid biosynthesis of AgNPs was achieved by addition of 1 mM AgNO3solution to the cell-free supernatant. The produced particles showed a single surface plasmon resonance peak at 400 nm by UV-Vis spectroscopy which confirmed the presence of AgNPs.Streptomycessp. SSHH-1E was identified asStreptomyces narbonensisSSHH-1E. Transmission electron microscopy study indicated that the shape of AgNPs is spherical and the size is ranging from 20 to 40 nm. Fourier transform infrared spectroscopy analysis provides evidence for proteins as possible reducing and capping agents. Furthermore, the biosynthesized AgNPs significantly inhibited the growth of medically important pathogenic Gram-positive and Gram-negative bacteria and yeast. The maximum biosynthesis of AgNPs was achieved at initial pH of 8, peptone of 0.5 g, and inoculum age of 48 h. The statistical optimization resulted in a 4.5-fold increase in the production of AgNPs byStreptomyces narbonensisSSHH-1E.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2082
Author(s):  
Katarzyna Antoniak-Jurak ◽  
Paweł Kowalik ◽  
Wiesław Próchniak ◽  
Robert Bicki ◽  
Grzegorz Słowik

The effect of La content and its incorporation route on physicochemical properties of ZnO/Zn(Al,La)2O4 or La2O3–ZnO/ZnAl2O4 mixed oxides with a spinel structure obtained from ZnAlLa Layered double hydroxides (LDHs) or ex-ZnAl LDH materials was investigated. The heterostructural nanocomposites with the similar Zn/Al molar ratio and varied La content were prepared by two techniques: via co-precipitation and thermal treatment of ZnAlLa LDHs at 500 °C or via incipient wetness impregnation of ex-ZnAl LDHs with aqueous solutions of lanthanum nitrate and subsequent thermal treatment. The obtained series of materials were characterized by the following techniques: X-ray fluorescence (XRF), N2 adsorption (BET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis with evolved gas analysis (TG/DTG/EGA), scanning transmission electron microscopy (STEM) energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and Fourier-transform infrared spectroscopy (FFT). The evaluation of activity toward the high-temperature water gas shift (HT-WGS) within the temperature range of 350–420 °C was carried out on the basis of rate constant measurements in the kinetic mode using a differential reactor. The co-precipitation technique allowed for a better distribution of La in bulk and on the spinel surface than in case of lanthanum incorporation via impregnation. ZnO/Zn(Al,La)2O4 or La2O3–ZnO/ZnAl2O4 mixed oxides were characterized by moderate activity in the HT-WGS reaction. The results reveal that introduction of lanthanum oxide over 2.4–2.8 wt% induces the phase separation of the ZnAl2O4 spinel, forming ZnO on the ZnAl2O4 spinel surface.


Author(s):  
Priyanka Mishra ◽  
Tanzeel Ahmed ◽  
Lalit Singh

Background: Silver nanoparticles (AgNPs) have been used in various medicinal products because of its anti-microbial properties. This research study has reported a simplistic, cost effective and eco-friendly method for the synthesis of Silver nanoparticles. Objective: The objective of present study was to compare the synthesis of silver nanoparticles (AgNPs) from various parts of Citrus maxima fruit like pulp, peel and seed. Methodology: The synthesized nanoparticles were characterized by the use of UV-visible spectroscopy, fourier transform infrared spectroscopy and transmission electron microscopy. Time-dependent synthesis of AgNPs was studied spectrophotometrically. UV–visible spectrophotometer was used to confirm the synthesis of AgNPs which showed maximum absorption at 410 nm, 420 nm and 430 nm respectively. Expected Results: Fresh peel extract exhibited the highest concentration of silver nanoparticles in comparison to pulp and seed. Fourier-transform infrared spectroscopy (FTIR) spectra analysis confirmed the presence of possible functional groups in AgNPs which can be responsible for reduction of nanoparticles. Morphological characters of AgNPs were analyzed using transmission electron microscopy (TEM) depicting the particles size as 12.58-47.80 nm. The antibacterial property of synthesized AgNPs was analyzed viz Escherichia coli (MTCC 1687) and Staphylococcus aureus (MTCC 902), specify them to be effective against both gram positive and gram negative bacteria. Conclusion: These results suggested that the fresh peel extract of Citrus maxima is a high-quality bioreductant for the synthesis of silver nanoparticles and have prospective for various biomedical applications.


2010 ◽  
Vol 14 (06) ◽  
pp. 540-546 ◽  
Author(s):  
Lingling Zhang ◽  
Yongtao Lu ◽  
Yukou Du ◽  
Ping Yang ◽  
Xiaomei Wang

Meso-tetrakis(p-sulfonatophenyl)porphyrin (TPPS4) functionalized platinum nanocomposites were synthesized and characterized using ultraviolet-visible absorption spectroscopy (UV-vis), fluorescence spectroscopy (FL), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD) methods. The postulated configuration of TPPS4 functionalized platinum nanocomposite may be described as an antenna system containing a photoreceptive TPPS4 shell and a nanosize platinum core. Fluorescence and photoelectrochemistry studies of both TPPS4 and the platinum nanocomposites showed that efficient electron/energy transfer occurred from the TPPS4 donor to the metallic nanocore acceptor. TPPS4 functionalized platinum nanocomposites are photocatalytic active for water reduction to produce hydrogen. The turnover numbers (TONPt and TONTPPS4) and quantum yield of hydrogen (ϕH2) for the photocatalyst (nPt:nTPPS4= 250) were 44, 11056, and 1.8%, respectively, calculated on the basis of the total amount of H2 evolution for 12 h irradiation.


2012 ◽  
Vol 625 ◽  
pp. 269-272
Author(s):  
Xiao Hui Fan ◽  
Hong Juan Liu ◽  
Yan Ming Chen ◽  
Ting Sun

A simple synthesis method of PVP (polyvinylpyrrolidone) coated ZnS QDS has been developed. The optical properties and morphology for the as-synthesized ZnS nanoparticles were characterized by UV-Vis absorption spectroscopies and transmission electron microscopy (TEM). The results show that PVP could act as a better stabilizer for the formation of ZnS nanoparticles in N, N-dimethylformamide. The obtained ZnS nanoparticles have spherical morphology and a narrow size distribution. ZnS nanoparticles could give an apparent extionic absorption peaks and quantum confinement effects.


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